Semiconductor power modules house one or more semiconductor power devices such as transistors or diodes, and can be used as components of a power circuit such as a converter or inverter. Ordinarily, the electrical terminals of the chip are wire-bonded to a metal leadframe at the periphery of the chip, and the chip and leadframe can be sandwiched between a pair of ceramic substrates that dissipate heat generated by the chip. The modules are normally constructed as flat rectangular packages that can be clamped against a cold plate (or heat sink), or even sandwiched between a pair of cold plates for double-sided cooling. In the latter case particularly, it can be difficult to ensure that there will be adequate electrical insulation between the metal leadframe of the module and the adjacent cold plates, especially in high voltage applications. A related concern arises in connection with large semiconductor transistor chips such as IGBTs and FETs where the gate terminal is coupled to segmented emitter or source terminals by an array of exposed conductive links because of the close proximity of the metal leadframe to the gate terminal links. Accordingly, what is needed is an improved semiconductor power module leadframe arrangement that is adequately insulated against inadvertent electrical shorting.